Implementing New Features on Steemit - Cancelling a Resteem and Private messaging

Some Ideas For a Better Steemit !

I had the idea of Cancelling Resteem because i made a miss-click and resteemed a post i don't wanted to. I looked for a ways to cancel that but don't found it, so I'm condemned to have this useless post on my blog for ever.
I think it's very problematic.
Deleting your own posts and comments can be interesting too, (or only before you had a upvote by someone other than you on it)

And a PM Box to send private messages

As this, if you want to say something to another user that don't need to appear to public, you can.

So if the administrators of Steemit can think about these ideas for me it's two important thing for steemit ameliorations.

Upvote if you think it's a good idea to gain a maximum of visibility !

And don't forget to comment even if you think it's not a good idea , say what you think why it's not good...